Single step repair of clear and opaque mask defects

The DRS II System was developed in response to continuous pressure from the semiconductor industry for an improved clear repair system for photomasks. We looked at a number of alternatives to the multi-step liftoff process before deciding on the laser-initiated decomposition of organometallic gases. The desire was to retain the technology of excess chrome removal using a laser zapper, proven in years of use at most mask makers and user installations, with an equally reliable method of missing chrome replacement.